Expanding and reprogramming the genetic code of cells and animals

Area of Science:

• Biochemistry
• Molecular Biology
• Synthetic Biology

Background:

• Genetic code expansion enables site-specific incorporation of unnatural amino acids into proteins.
• Orthogonal systems, including ribosomes and synthetase/tRNA pairs, are crucial for this process.
• Progress has been made in applying these techniques in various organisms.

Purpose of the Study:

• To summarize recent advances in genetic code expansion and reprogramming.
• To highlight methods for enhancing unnatural amino acid incorporation efficiency.
• To discuss the expansion of the repertoire of site-specifically encoded amino acids.

Main Methods:

• Creation and evolution of orthogonal ribosomes.
• Genome manipulation for enhanced unnatural amino acid incorporation.
• Discovery and engineering of mutually orthogonal synthetase/tRNA pairs.
• Development of the pyrrolysyl-tRNA synthetase/tRNA pair for eukaryotic applications.

Main Results:

• Enhanced efficiency in unnatural amino acid incorporation.
• Increased number of distinct unnatural amino acids that can be site-specifically encoded.
• Successful application of genetic code expansion in eukaryotic cells and model organisms (C. elegans, D. melanogaster).
• Facilitation of posttranslational modifications and imaging via chemoselective reactions.

Conclusions:

• Genetic code expansion is a powerful tool for protein engineering in diverse biological systems.
• Continued development of orthogonal systems and decoding mechanisms drives progress in the field.
• The ability to incorporate diverse unnatural amino acids opens new avenues for protein functionalization and application.